Plug-type control valve for fluidized catalyst conversion system



1954 H. KERSHAW ET AL PLUG-TYPE CONTROL VALVE FOR FLUIDIZED CATALYSTCONVERSION SYSTEM 5 Sheets-Sheet 2 Filed Nov. 23, 1948 walk-n INVENTORSHAROLD KERSHAW E DWARD o. DOWLI N6 ATTORNEYS 1954 H. KERSHAW ET ALPLUG-TYPE CONTROL VALVE FOR FLUIDIZED CATALYST CONVERSION SYSTEM 5Sheets-Sheet 3 Filed Nov. 25, 1948 FIG. 5

FIG.4

FIG.7

FIG.6

INVENTORS HAROLD KERSHAW EDWARD D. DOWLI NC ATTORNEY S Feb. 9, 1954 H.KERSHAW ET AL 2,668,755 PLUG-TYPE CONTROL VALVE FOR FLUIDIZED CATALYSTCONVERSION SYSTEM Filed Nov. 25, 1948 5 Sheets-Sheet 5 FIG. [2

INVENTORS HAROLD KERSHAW EDWARD D. DOWLING 39 a :5. flam ATTORNEYSPatented Feb. 9, 1954 assist PLUG-TYPE oonrno IZED CATALYST o L VALVE QRsmit- ONVERSION SYSTEM er Edge, Edward D, Dowling Queiis Village,.N.,Y,,assignors to The ,Kcllogg com p'aiiy, Jersey City, N. J'.,

a corporation of Delaware Armenian Noeimiir 23, 1948; Serial No. 61,6223 Claims. (01. 123L28) This invention relates to a control valveandparticularly to a plug-type control valve forcon; trolling the how offluids or fiuidized material through a conduit, such as the powderedcatalyst transfer lines arid the flue gas vent stacks en1 ployed influid catalytic cracking systems in the petroleum refining art. 7 a vvWhile the invention is capable of various applications involving hightemperature operations in the chemical processing and petroleum refining arts it will be referred to and explainedin the followingdescription as being particularly ap plied to a converter, uch as afluid catalytic cracking unit of conventional design, havingsuperimposedcontact chambers in which the catalyst is maintained in a state of phaseseparation comprising an upper diffuse phase and a lower densepseudo-liquid phase, the, catalyst being withdrawn from the lower densephase 01 the upper chamber through a vertical internal stand; pipe anddischarged at a low point. within the dense phase' or the lower c amberand, after suitable treatment in the lower h mper, being returnedupwardly through an iii rn'al icaI carrier the to the dense e: the upperIn systems or this type, aciontinufous' cycle. of catalyst between thechambers is ob passing catalyst by gravity new fro'i chamber tothe lowerchamberthrou'gh I pipe and passing the catalyst rom the 1s r chamber tothe upper chamberthroug'h I line by injection thereina stream of hycroce bons', the continuous now of therr'ljixtiure' um wardly through thecarrier line resul from the fact that the vaporous hydroc'a ons in v epresence of the hot catalyst form a l V x 1ef lower particleconcentration within thecar1 line than is present in the dense bed ofcatalyst in the lower chamber. I, p

Suitable flow control of catalyst from" the stand-pipe into the densephase of thjcll'ovier chamber and from the latter into the carrier linefor conveyance into the upper chamber j .s 0b" tained by the use of plugvalves engageable with the lower ends of the transfer lines andhavingelongated valve stems extending thl ugh the vessel wall controlled theirlongitu'di al m'ov'ement by external mechanical or manual operatingmeans. H V

Because of the extreme lengthof the" vessels or chambers employed incarrying out such chemical conversions. the long standpipes and carrierlines re I u t rr w. fi n rs et efia er. siderable expansion andcontraction under the tofiran f er, ,ther atab'st- 2 y extremetemperaturesv normally employed. The problem of pipe line expansion musttherefore be considered, since it is not unusual for an expan: sion of 3to 4 inches to occur in the internal transfer pipe lines .loetween theextreme position at: startingup temperature and the position attainedwhen the chamber is at the desired operating temperature. p i l To avoidundue stressing or buckling of the transfer lines, the vessel walls, andthe valve mechanism under all conditions of operation, il'ariousexpedients have heretofore been employed to permit outward movement orrelease of the valve when thermal expansion the transfer line occurswhile the valve member is in its closed position, as where the chamberis brought up to operating temperature conditions with the; plug valvesinadvertently closed or not siifiiciently retracted. V

The present invention is in the nature of an improvement in theplug-type valve assembly, whereby such expansion forces are permitted tobe absorbed within the external valve control mechanism. K I V Aprincipal object of the invention is to provide a unitary plug-typecontrol valve for the endof a powdeiitran's'f e'r lii'ie Within achamber, adapted to accommodate therein expansion tlieiih' accompanyinga temperature rise while the valve is" in its closed posit on, S0constructed to be readilyremovable as a single unit for replacement,inspection or repair with a riiiniii'ium of dismantling operations. v

Another object is to provide a unitary plug: typecontrol valve for theendof a powder ti'aris fer ,liiiewithin a chamber, adapted to readilyaccommodatethermal' expansion in the line as; cblfnpanyirig' atemperature rise while the valve is inits closed position, and having ahollow stem through which a feed stream of i' luidmaterial to be treatedmay be continuously injected from an .e'riternal source into the end ofthe transfer use. the valve b'ein'ggo constructed that movement of thevalve member between its extreme positions may be" elfecteol withoutcausing anysu'bstantial 45" stressing ermovement of the line connectionsfor supplying the fluid material to the hollow stem of th'evalv'e. I

Afufther object is to provide a unitary plug; typecofitrol valve for theend of a powder trans; fer line' within a chamber, adapted while in itsclosed position to accommodate thermal expansioninthe line, and having ahollow stein e3":- tendingthrough the chamber. wall connectedto' asource of fluid materia-Land toan external Opesating mechanism forcontrolling the movement of said valve, the construction being such asto require a minimum of effort for movement of the valve member.

Another object is to provide a unitary plugtype control valve for theend of a powder transfer line within a chamber having its body portionrigidly secured to the transfer line and extending to a point outsidethe chamber, and its valve member adapted to accommodate thermalexpansion while in its closed position.

Still another object is to provide a unitary lugtype control valve forcontrolling the flow of fluid from a chamber into a conduit, in whichthe movable valve element is controlled externally of the chamber and isadapted to accommodate thermal expansion in the valve stem occurringwhile the valve is in closed position.

Other objects will be apparent from a consideration of the followingdescription taken in connection with the accompanying drawings forming apart of this application, in which;

Fig. 1 is a fragmentary elevation, in partial section, showing thevalves of the present invention applied to a chamber or vessel which maybe considered to be part of a typical fluid catalytic cracking unit comrising an upper reaction chamber and a lower regeneration chamberconnected by internal transfer lines terminating in the lower portion ofthe lowerchamber, portions of the unit not directly cooperating with thevalve members being omitted for the sake of clarity, since they form nopart of the present invention;

Fig. 2 is an enlarged view in partial section of the center valve ofFig. 1, excluding the operating means, used in connection with thecentral transfer line for passing the oil feed and fresh regeneratedcatalyst from the lower regenerating chamber to the upper reactionchamber;

Fig. 3 is a side sectional view of Fig. 2;

Figs. 4, 5, 6 and '7 are enlarged sectional views taken along the lines44, 55, 6-6 and 'I'I, respectively, of Fig. 3;

Fig. 8 is a sectional elevation showing a modification of the valvehead;

Fig. 9 is a sectional elevation showing a modified form of the valve;

Fig. 10 is a fragmentary section of the valve mechanism of Fig. 9immediately below the line A-A;

Fig. 11 is a sectional elevation showing a modified form of valveguide-sleeve;

Fig. 12 is a sectional elevation showing a modification of the valveadapting it for use in controlling the discharge of flue gas through avent stack.

Referring to Fig. 1 of the drawings there is shown in fragmentarysection the lower portion of a chamber II, which may be the lower of twoseparate superimposed vessels or the lower subdivision of a singlevessel suitable partitioned to form upper and lower chambers, such asthat disclosed in U. S. patent application Serial No. 724,956, filedJanuary 29, 1948. For the purposes of illustrating an application of thepresent invention it may be assumed that the chamber II represents thelower regeneration chamber of a fluid catalytic cracking unit having asuperimposed reaction chamber, as shown in the abovementioned pendingapplication. Vertical conduits I2 and I3 serve as lines of communicationbetween a dense fluidized mass of catalyst maintained in the bottom ofthe upper reaction chamber and a similar mass I4 maintained in the lowerportion of the regeneration chamber. Conduit I2 is a carrier line forconveying fresh regenerated catalyst from the dense fluidized catalystmass I4 maintained in the lower portion of the chamber II upwardly intothe reaction chamber above, and conduit I3 is a stand-pipe forwithdrawing spent catalyst from the dense bed maintained in the lowerportion of the upper reaction chamber and discharging it into thecatalyst bed or dense phase I4 of the regenerator.

Since a superimposed arrangement of reaction and regeneration chambersin a fluid catalytic conversion unit is well known, a fullerillustration and description is not believed necessary for a completeunderstanding of the present invention.

The carrier line I2 and the stand-pipe I3 are elongated conduitsextending upwardly through the regeneration zone in chamber II and are,therefore, subject to considerable expansion and contraction between theextremes of temperature obtained when the regenerator is brought from acold condition up to operating temperature conditions which may be inthe order of about 1000 to 1100 F.

A cylindrical member I5 centrally positioned in the bottom of thechamber II forms a well I6 into which the lower end of the regeneratedcatalyst carrier line I2 extends. Suitable guide members I! attached tothe inner wall of the cylinder I5 serve to maintain the lower end of thecarrier line I2 centrally positioned within the well without restrictingits free longitudinal movement by reason of expansion or contraction asa result of temperature changes within the regenerator. The lower end ofcarrier line I2 is provided with an outwardly flared mouth portion I8,the inner surface of which provides a seat for a plug-type valve.

The lower end of stand-pipe I3 terminates below the upper edge of thecylinder I5 in the annular space surrounding the well I6, and issimilarly provided with an outwardly flared mouth portion I9 for thereception of a plugtype valve. Guide struts 20 pivotally attached attheir ends to lugs 2i and 22 secured, respectively, to the outer surfaceof the stand-pipe I3 and the inner wall surface of the chamber II serveto maintain the lower end of the stand-pipe I3 in axial alignment withthe plug valve under all temperature conditions.

In the lower portion of chamber II a horizontal annular grid 23 isprovided, suitably supported by a ring 24 attached to the chamber walland a ring 25 attached to the outer surface of the cylinder I5, tosupport the dense phase mass of regenerated catalyst. A steam inlet 26extends through the lower wall of the chamber II into the well and isconnected at its inner end to a pipe distributor ring 27 from whichsteam is introduced into the well I6 to pass upwardly through the massof catalyst descending into the well from the dense bed I4 of theregenerator for subsequent passage into the lower end of the 5 the valveis intended for fluid injection into a powder transfer lineconcomitantly with flow control of the powder into the same, asexemplified by the internal catalyst carrier line 12 for conveyingcatalyst withdrawn from the lower regeneration chamber H, in admixturewith vaporous hydrocarbons injected through hollow injector head 32directly into the carrier line, to an upper reaction chamber, thecatalyst being transferred continuously between dense fluidized massesin the lower portions of the chambers. The valve is equally suitable,however, with only slight modification for use in controlling thetransfer of catalyst through a stand-pipe from an upper regenerationchamber to a lower reaction chamber concomitantly with injection ofhydrocarbon feed into the latter. The valve head in such case ismodified as shown in Fig. 8, so that the hydrocarbons may becontinuously injected directly into the reaction chamber adjacent thepoint of introduction of regenerated catalyst. Valve 31] controls theflow of spent catalyst through the stand-pipe l3 connecting an upperreaction chamber with the lower regeneration chamber H. is modified bysubstituting a solid plug head 33 for the hollow injector head 32, andby eliminat ing or blocking off the inlet nozzles which supply to thebonnet of the valve the fluid to be injected into the transfer line. toprovide aeration gas to the stand-pipe [3, the hollow type injector headand the inlet nozzles may be retained to supply gas, such as steam, tothe stand-pipe. Regardless of whether the valve is to be used forcarrier line control or for stand-pipe control, or whether the valve isto be used as a combined plug valve and injector or solely as a plugvalve, the basic construction illustrated in the drawings may be used.The slight changes necessary to adapt the basic valve structure for itsparticular use may readily be made at the place of manufacture or in thefield with a minimum of cost, materials, and labor.

As a safety precaution to avoid injury to transfer lines l2 and I3 inthe event that valves 3!! and iii are left in closed position while thetemperature of the unit is substantially increased, as in starting upfrom cold condition, means are provided in conjunction with the externalvalve control mechanism to accommodate or relieve the severe stressestransmitted to the valve stems from the expanding transfer lines, andincidental stresses transmitted to the valve assembly as a result ofexpansion of the valve stem.

Valves til and 35 are unitary assemblies projecting through the bottomof the chamber l I in axial alignment with their respective catalysttransfer lines l3 and i2, and are removably attached to the chamber wallso that they may readily be removed as a unit. For this purpose, flangedmounting nozzles 34 and 35 are. provided in the bottom of the chamber IIto receive the valve units it and 3|, respectively. The entire valvemechanism is supported from nozzles 34 and 35 by the flange 36 of valvebonnet 37 forming a closure for the end of the mounting nozzle and beingremovably secured thereto in any conventional manner.

The valve assembly 3i, shown in enlarged section in Figs. 2 to 7,comprises an elongated valve stem consisting of a tubular portion 38,having the injector head. 32 secured to its upper end engageable withthe. mouth portion 18 of the carrier line, and a solid rod portion 39connected tothe lower end of the tubular section 3'8through The valve39, however,

If it is desired, however,

a spider 4!! having openings M which provide free access to the hollowportion 38 of the valve stem. Spider 4c is secured, as by welding, tothe lower end of hollow portion 38, and is removably joined to the upperend of solid portion 39 by the screw collar 42 threaded into the lowerend of the spider. Bonnet 377 forms a chamber into which the oil feedand, if desired, a steam and slurry mixture may be introduced throughdia metrically opposite inlet nozzles it and 34 set in the sides of thebonnet.

The upper end of bonnet 3? is extended to form a cylindrical valve guidesleeve is projecting upwardly into the chamber H to a point adjacent thelowermost position of the valve head 32 when the valve is fullyretracted. Upper and lower guiding and sealing surfaces id and All areprovided on the inner wall of the valve guide sleeve 45 separated by anannular space between the guide sleeve and the hollow valve stem intowhich bleed steam may be introduced by steam line 49, the arrangement ofwhich is clearly shown in Fig. 4. The lower guide portion is undercut asubstantial distance from its upper end to provide an annular space asinto which bleed steam may be introduced through line lli without directimpingement on the hollow valve stem 33.

The portion of valve guide sleeve d5 below the surface il forms with thebonnet a continuous chamber within which the portion of the valve stemincluding the spider iii moves up and down between its upper and lowerlimits. Constant open communication for any position of the valve stemis thus provided between the hollow portion of the valve stem and thebonnet 3i into which the oil feed is introduced through inlets and M. Aparticular advantage of the arrangement thus far described is that thenozzles t t and M, connectable with external feed lines, not shown, areat all times in nxed position regardless of any movement of the valvestem, thus eliminating the need for the usual flexible couplingarrangements between the valve and the oil feed lines.

The valve guide sleeve portion of the bonnet 37 extending upwardly fromthe flange 38 is provided with a cylindrical insulation casing 5| secured at its lower end to the upper face of the flange 35. The annularspace between the casing 5| and the valve guid sleeve as is filled witha suitable insulation material 52, such as mineral wool cement. Embeddedwithin the insulation material 51 is the steam bleed line d5, whichextends downwardly through the insulation material and partiallyencircles the valve guide sleeve before communicating with a radialinlet port 53 formed in the flange The insulation. material may suitablybe applied to the valve unit at the point of manufacture.

At the lower end of bonnet 3? a cover plate 55 is provided to seal thebonnet chamber. A. conventional packing gland 55 is provided in coverplate 54 to receive the solid portion iii of the valve stem. A. suitablelubricant line is provided in the usual manner, as at 55, to lubricatethe packed portion of the gland.

A support member, conveniently formed as a flanged cylinder iil havingcut out portiens'slt and 59 at each end, is removably attached to theunderside of the bonnet flange encircling the bonnet 3] and the portionof the valve stem projecting downwardly through cover plate fhe flange-dnozzles forming the feed inlets til it Of the bonnet 3i extend outwardlythrough the openings 53 in the upper end of the cylinder 51'. Theopenings 59 in the lower end of cylinder 5% permit'free' access to thepacked gland 55 set in the cover plate 54 and receiving the solidportion 39 of the valve stem. The lower end of cylinder 51 is providedwith an extended flange 51 having a series of openings to receivedownwardly projecting spring bolts 62 of a series of preloaded springassemblies, generally indicatedby the numeral 63, distributed about theupper surface of the flange Bl, as shown in Fig. 6. The springassemblies 63 may be separately constructed as preloaded units, eachcomprising a cylindrical casing 64 containing a coil spring 65surrounding the spring bolt 62, which is threaded at both ends. lhespring 65 is held under compression between the lower end 66 of thecasing 6t and an upper spring washer 67. Upper washer 61 is restrainedfrom upward movement by the ring 69 attached, as by welding, in theupper end of casing 64. Spring bolt 62 is threaded at both ends, thelower threaded portion being of slightly reduced diameter to provide ashoulder. A nut 68 on the upper end of the spring bolt is adjusted toprovide a desired amount of extension of the bolt from the lower end ofthe spring assembly. Each spring assembly is adjusted so that theshoulder portions at the lower threaded ends of the spring bolts areuniformly spaced from the lower end of the spring casing. When thedesired adjustment of nuts t8 has been made,

each nut may be tack-welded to its spring washer 3 61. The reason foruniform extension of the lower ends of the spring bolts will beexplained hereinafter in connection with the attachment of the valvestructure to the operating devices.

With the exception of the movable valve stem, the structure thus fardescribed is rigidly supported from the flanged nozzle 35 of chamber llthrough the bonnet flange 36, and the valve stem formed by connectedportions and 353 is free to move toward or away from its seat on the endl8 of the carrier line 52 through the packed joint 55, which preventsleakage of fluid from the bonnet chamber. The lower end of solid portion39 of the valve stem extends below the flange 6i and is adapted forattachment to a commercial valve operator. The valve operator inder,generally indicated by the numeral H,

and a manual operator, generally indicated by the numeral 12, is shownin elevation in Fig. 1. Figs. 2 and 3 show in section only such portionsof a conventional hydraulic cylinder as would require modification inorder to adapt it for connection with the preloaded spring assembly. Theoperation and construction of hydraulic cylinders for such use beingwell known, the usual feed lines and valves ordinarily associated withthe hydraulic cylinder have been eliminated for the sake of simplicity.

A modified cylinder cap l3 is provided at the flanged upper end of thecylinder body of hydraulic cylinder ll through which the lower end ofthe solid portion 3d of the valve stem projects into the interior of thecylinder. A fluidtight connection is provided between the cylinder capand the valve stem by a conventional packing gland i4. Cylinder cap 13is provided with a series of openings through which the lower ends ofspring bolts 62 may extend.

Bosses T5 are provided on the upper surface of the cylinder cap 13around the spring bolt openings to provide breakaway contact surfaces,

normally held against the under side of the flange 6| by the springassembly. Slightly less than the full length of the lower threadedportion of spring bolts 62 is permitted to extend through the openingsin the cylinder cap i3. Nuts 1% on the lower ends of spring bolts 52secure the cylinder cap '13 to the flange 3|. The spring bolt nuts '16are advanced on the lower threaded portion of the spring boltssufficiently to contact the shoulders and to transfer the spring loadfrom the spring stop rings 69 in the upper ends of the spring casings tothe spring bolts through the spring washers 67, retained by the nuts 63on the upper ends of the spring bolts.

To maintain constant axial alignment between the valve mechanism and thevalve operator mechanism, guide means is provided between thecylindrical support member 57 and the hydraulic cylinder cap it. Forthis purpose, a cylindrical member 69 may be attached at its lower endto the upper surface or" the cylinder cap 73 and extend telescopicallywithin the cylinder 57. Openings ii are provided in the lower portion ofthe cylindrical member 66 to normally align with the openings 5?? in thelower portion of the cylinder 5?, thus permitting ready access to thepacking glands 55 and 74.

The lower end of solid valve stem portion 39 terminates within thehydraulic cylinder ll and is threaded into the connector extension E8 ofthe piston 59. The piston ill of the hydraulic cylinder is attached by athreaded connection to the up er end of the stem 80 of manual operatorl2, which extends upwardly into the hydraulic cylinder through lowercylinder cap 81, provided also with a packing gland 82.

The lower end of operator stem 80 extends downwardly through the yoke85% of the manual operator and is threaded at its lower end to receivethe yoke sleeve 84 mounted for free rotational and limited longitudinalmovement in the lower end of the yoke, and operated by the hand- Wheel85. The free longitudinal movement of the yoke sleeve 84 corresponds tothe stroke of the cylinder piston 79.

In normal operation, the valve stem is actuated along its longitudinalpath of movement toward or away from its seat on the lower end of thetransfer line by movement of the piston '19 within the hydrauliccylinder 'I'I in response to pressure changes within the hydrauliccylinder on either side of the piston controlled through the usualinstruments associated with hydraulic valves, not shown.

When hydraulic operation of the valve is for any reason impossible, orwhen it is desired to manually change the position of the valve, thehand-wheel 85 may be rotated until either end of the yoke sleeve 8d,dependent upon the direction of rotation, is brought into contact withthe end of the yoke. Further rotation of the yoke sleeve will then causethe stem 80 and its associated portions 38 and 39 to be movedlongitudinally to open or close the valve 552. Free movement of thepiston I9 within the hydraulic cylinder, during manual operation of thevalve, is obtained by by-passing the fluid oil of the hydraulic cylinderto equalize the pressure on either side of the piston, so that movementof the piston merely causes the oil to pass from one end of the cylinderto the other. Such lay-passing may be effected through the conventionalcontrol instruments, not shown, associated with the hydraulic cylinder.

While the valve mechanism has been shown as being operated through acombination hydraulic and manual operator, it is obvious that variousother means for positively actuating the valve stem may be employed.When a combination motor-driven and hand-operated device is to be usedfor actuating the valve stem, the cylinder cap 13 and its associatedpacking gland 14 may be replaced with a suitable mounting plate, throughwhich the lower end of valve stem portion 39 may freely pass and beconnected at its lower end to the actuating means. In any case, however,the operating mechanism is suspended from the spring bolts 62 and thecylinder cap I3, or mounting flange, as the case may be, is normallyheld in contact with the flange 6|.

For all normal operation of the valve, the entire assembly remains as asinglerigid unit, from the upper end of the guide sleeve 45 to the lowerend of the yoke 83 of the manual operator, and the valve stem, includingthe hollow portion 38, the solid portion 39, and the operator stem 80,which forms a continuation of the valve stem, is movable along a path inaxial alignment with the carrier line 12. The breakaway connectionbetween the flange 6| and the cylinder cap 13 is provided primarily as asafeguard against injury to the carrier line, the chamber walls or thevalve mechanism when the temperature within the chamber H is raisedsufliciently to cause a substantial expansion in the carrier line whilethe valve head 32 is in closed position against its seat l8. In suchevent, the expansion forces exerted by, the carrier line tend to forcethe valve downwardly. If, at the time, the valve i under hydraulicoperation, the piston 19 resists such movement and the entire operatingmechanism, as a unit, is forced downwardly against the action of thesprings 65 of the spring assembly. This causes a breakaway between theflange BI and the cylinder cap 13, the latter moving downwardly adistance equal to the longitudinal expansion of the carrier line and thevalve stem. When the valve is under manual operation, at which timepiston 19 is free to move within the hydraulic cylinder, a breakawaybetween the valve mechanism and the operating mechanism will depend uponthe position of the yoke sleeve 84. Since the yoke sleeve 84 is free tomove longitudinally within the hearing at the end of the yoke :23, thevalve stem will move freely downward, carrying the yoke sleeve with it,until the latter is in its lower limiting position. Further movement ofthe valve stem will then cause a breakaway between the valve structureand its operating mechanism.

As previously mentioned, an advantageous feature or the valve is that itmay be removed as a unitary structure from the chamber wall by simplyremoving the bolts or other connectors joining the flange 36 to theflanged nozzle 35. Since such valves are of considerable size andweight, and are consequently costly, the problem of removal withoutinjury to the valve is important. To facilitate such removal, two of thefour reinforcing webs 86 attached, as by Welding, to the cylinder 51 andto the flange between the spring casing members 64 are provided withextensions 87 at their upper ends to form lugs having openings 88 towhich a suitable hoisting apparatus, not shown, may be attached.

It has been assumed, for the purpose of demonstrating a typicalapplication of the present invention, that the hollow valve is employedin connection with the lower end of a carrier line for transferringcatalyst from a lower regeneration zone to an upper reaction zoneinjecting the hydrocarbon oil feed from the hollow tip of the valve intothe carrier lin however, is also adapted for use in catalyst is to beconveyed from an er regeneration zone into a lower reaction zone througha stand-pipe In such application, a valve head. constructed as shown inFig. 8 may be attached to the upper end of the hollow portion 38 of thevaive-stein to control the flow of regenerated catalyst from thestand-pipe into the reaction zone, while continuously injecting ahydrocarhon feed through the head of the valve into the reaction zone ata point adjacent the lower end or the stand'pipe. Referring to Fig. 8, amodified valve head til having a solid plug tip and side ports a isattached to the upper end of the hollow portion 3'5 of the valve stem.Conw stant open communication between the valve stem and the reactionzone is thus provided regardless of the position of the valve. Thedescending stream of fresh regenerated catalyst emerging from the lowerend of the stand-pipe when the plug head is retracted merges with thehydrocarbon feed stream discharging laterally from the valve headthrough ports at to provide rapid and erficient intermixing of thecatalyst and the oil.

Figs. 9 and 10 show a modification of the in vention in which the bodyof the valve is reniovably secured to the lower end of the carrier lineIt, so that any longitudinal movement of the carrier line as a result ofexpansion or contraction will cause a corresponding movement of thevalve structure as a whole inwardly or outwardly with respect to thevessel wall. A suitable stufling-box or packing gland arrangement isprovided between the body of the valve and the chamber I l to adequatelyseal the joint while permitting longitudinal movement of the entirevalve unit, as clearly shown in Fig. 9. In the illustration of themodification, reference numerals used in connection with Figs. 1 to 7will be repeated to designate similar parts.

Referring to Fig. 9, the valve stem of Fig. 2', consisting of theinjector head hollow por tion 33 and solid portion 39 connected theretoby spider it is shown in closed position against the lower end ofcarrier line 52. A modified mouth portion at, having a series of lugs 92distributed about the outer perimeter is used in place of the flaredmouth portion 58 to provide a seat for the valve head 32 and means forsecuring the valve unit to the carrier line.

The cylindrical bonnet 3'1? having fluid inlets 43 and 44 adjacent itslower flanged end is provided with a modified valve guide sleeve $53 atits upper end to guide in free longitudinal move-- ment the hollowportion 38 of the valve stem. Valve guide sleeve 93 is substantiallygreater in diameter than hollow valve stem. portion .35, so that anannular space ed is provided for the circulation of bleed steam. Upperand lower contact surfaces 55 and 35 are provided in each end of guidesleeve 53, each being undercut for the major portion of its length toform annular spaces ill and :38, respectively, communicating with theannular space 9 Ports are provided in the wall of guide sleeve 93adjacent lower annular space 95%, so that bleed steam may be introducedtherein without direct impingement on the valve stem. Lower contactsurface 98 maintains contact with the lower end of holw valve stemportion 38 above the spider 39 when the valve is moved to its closedposition, so that the remaining portion of bonnett'i forms a chamberwithin which the spider portion 46 moves up and down for the full lengthof the valve stroke, constant open communication being at all timesprovided between the bonnet chamber and the openings M in the spider.

The bonnet 3i and its upper valve guide extension 93 presents acontinuous outer cylindrical surface extending into the chamber I!through the flanged nozzle provided in the wall of the chamber II inaxial alignment with the valve stem and the transfer line I 2. A coverplate I9I, having a central opening to receive the upper end of thebonnet, is removably secured to the nozzle 35. A cylindrical neck Hi2formed about the perimeter of the central opening in plate IiiI extendsupwardly from the plate through the nozzle into the chamber H to form astufiing-box through which the cylindrical body formed by the bonnet 9iand its guide sleeve extension 99 may slide longitudinally while aconstant fluid-tight seal is maintained. The upper end of neck I92 isincreased in wall thickness for a short distance to provide a base forthe stufiing-box and a contact surface IE3 for guiding the valve guidesleeve 99.

The elongated stuffing-box formed by the annular space between thecylindrical member I92 and the surface of bonnet 3?, including itsextension 93, is provided with suitable packing material I M and I95 ateach end, separated by a lantern gland I95. The ports 99 provided in thewall of the member 93 communicate with the space occupied by the lanterngland IE5 at all times. A line I91 conveys bleed steam from an inletport I98 formed in the cover plate IISI to the space occupied by thelantern gland Its": through an opening I99 formed in the wall of thecylinder I02. Lantern gland I95 is of open-work construction, to permitfree passage of the bleed steam through the lantern member and the valveguide sleeve ports 99 to annular space 94.

Nozzle 35 is of substantially greater diameter than stuifing-box neckI62 to provide an annular space to receive suitable insulation material.For this purpose, a cylindrical casing III is attached along its lowercircumference to the cover plate I ill and extends upwardly through thenozzle 35 and the wall of the chamber II. The casing II I is of as largea diameter as may be freely received within the opening of the nozzle'55. Suitable insulation material II2 is packed between the casing I IIand the cylinder I92, within which the bleed steam line I9? iscompletely embedded. The stuffing-box is provided with a conventionalgland H3 attached to the cover plate IQI by stud bolts II.

On the upper end of valve guide sleeve 93 is a flange member H5, rigidlysecured to the guide sleeve and reinforced by braces or webs I I6.Tiebolts II'I extend through aligned bolt holes in the flange H5 and inthe lug members 92 formed on the perimeter of the mouth portion 91 ofthe transfer line I2. The threaded portions at the ends of tie-bolts II! are of reduced diameter to provide shoulders held against the flangeI I5 and the lugs 92 by nuts H8 and H9, respectively, on the threadedportions of the tie-bolts. The coupling arrangement between the lowerend of the carrier line I2 and the valve is, therefore, such that thevalve moves as a unit with the carrier;

12 line during movement of the latter in either di rection.

A breakaway joint as provided in the illustration of Figs. 2 and 3 isnot required in the modification of Figs; 9 and 16 since the entirevalve structure in the latter illustration moves longitudinally througha stuffing-box in the cover plate IfiI upon expansion or contraction ofthe carrier line I2. The hydraulic and manual operators may therefore berigidly attached to the body of the valve through the flange I2I on thelower end of bonnet 3'5. A cover member I22 attached to flange I2I andhaving conventional stuffing-box arrangements I23 seals the lower end ofthe bonnet 3'1.

While the modification of Figs. 9 and 10 eliminates the need for abreakaway between the body of the valve and its operator as a result ofcarrier line expansion, there is still to be considered the matter ofvalve stem expansion and the stresses created in the valve stem when thevalve is left closed during a substantial temperature rise. To relievethe stresses in the valve stem, a springloaded connector I24 is providedbetween the lower end of valve stem portion 39, extending below packinggland 23 is member I22, and the valve operating mechanism. Spring-loadedconnecter E24 is situated within an elongated spacing member I25attached at its upper end to the bonnet cover member 522 and, in turn,forming at its lower end a cylinder cap for the hydraulic cylinder ll.Spring ccnnecter I24 comprises inner and outer telescoping members I26and IN, respectively, normally held in extended position against aninternal stop ring I28, secured, as by welding, in the outer end of themember I2'I, by the action of a pair of compressed coil springs I 29 andI3I concentrically arranged Within the inner telescoping member I26. Theupper closed end I32 of member I28 is connected to the lower threadedend of valve stem portion 39,'and the lower closed end I33 of member I2!is connected to the upper threaded end of a stem portion I34, the lowerend of which passes through a packing gland I35 in the base of spacingmember I 25 into the hydraulic cylinder II where it is connected to thepiston I9 attached to the upper end or stem 80. Expansion of the valvestem is accommodated by the compression of springs I29 and I3I, thusavoiding injury to the valve mechanism.

The provisions for expansion providedin the .valve of Figs. 2. to 7differ from those provided in the modified valve structure of Figs. 9and 10. Whereas in the former, the body of the valve remains fixed withrespect to the chamber while the valve stem and the operating mechanismrigidly connected therewith yield to the expansion forces applied at theend of the closure member against the action of the spring assembly, inthe latter the body of the valve remains fixed with respect to the endof the expandible carrier line and moves as a unit therewith, while thevalve stem is rendered axially compressible by inserting a resilientconnecter in an intermediate portion of the valve stem.

While it may seem that the modification of Figs. 9 and 10 is notstrictly in keeping with the recited objectives of permitting a minimumof movement of the feed line connections leading to deviation from theseobjectives in the modified construction. In either case, the forcerequired to operate the valve stem is maintained at a minimum by havingthose portions "of the valve stem frictionally engaged within thestoning-boxes at the lower end or the valve bonnet and at either end ofthe hydraulic cylinder of a minimum circumference. This is accomplishedby providing a solid rod of reduced diameter for the lower portion ofthe valve stem. In the modification of Fig. 9, however, the guide sleeveportion or" the valve body moves within the stuffing-box formed by thecylinder 162. Such movement is readily accomplished. by the thermalexpansion forces in the carrier line, which are easily sufiicient forthis purpose. Furthermore, fluid inlet connectors 33 and 4d move up anddown with movement of the valve body. Such movement, however, is not inexcess of the maximum possible expansion of the carrier line, which isnormally not more than about three or four inches. Standard lineconnections are capable accommodating this amount of expansion.

Fig. 11 shows a mod fication of the valve guide sleeve in which thesteam bleed line for introducing steam into the annular space betweenthe hollow portion or the valve stem and the .a-nmdar space formedbetween the guide surfaces it? and I38. Grooves 139 formed in the guidesur-- faces 13? and i258 are provided with piston rings Ml which areexpanded to encircle the hollow valve stem. and provide an eiiectiveseal against the passage of catalyst from the chamber ii or oil from thebonnet 3?.

In addition to the advantageous application of the valve of the presentinvention to the control of catalyst flow in the transfer lines of fluidcatalytic conversion systems, we have found the valve to be suitablyadapted also for the control of flue gas discharging from a conversionsystem through a vent 0r stack.

It is the usual practice such systems to locate the hue gas controlvalves in the base of a stack which vents to the atmosphere the gasesdischargin from the outlet an electrical dust precipitator or fromcyclone separators located within the regenerator. valve or valvescontrol the flow of dust laden gases by selectively reducing orenlarging the area through which the flow, are usually actuated inresponse to pressure regulating instruments, not shown.

He'etcfcre, the valves employed for this purvalve, co. prising twohorizontally placed flat 7 plates sliding across a central opening insuch a manner as to keep the flow substantially central with respect tothe conduit.

Experience has shown the catalyst powder in concen ions usually found insuch flue gas streams does not produce serious erosion unless highvelocities are employed, and then. primarily at the points streamdeflection. Such conditions are obviously at their maximum withinrestricted valve port openings and immediately downstream therefrom. Forthis reason, the valve :3 in such areas are usually of reinforcedthickness or or" a material especially resistant to such erosion, inorder to afford maximum life.

Referring to Fig. 12, the valve is shown. at the lower end of a stack,which may be assumed to be the stack of a fluid catalytic cracking unitmounted adjacent the regenerator and receiving 1 streams -oriiue gastherefrom through side inlets. Only a fragmentary portion of the'stackand its connections with the regenerator have been shown, sincefurther illustration is not believed essential for an understanding ofthe invention.

The lower end of vertical stack M2 is provided with a cover plate orhead having a central connector hit and diametrically opposite inletsI55, connected as above mentioned to the regenorator.

The stack. is part ioned immediately above the flue gas inlets i iii bythe inverted semi-ellipsoidal member l iii having a central openingprovided with a relatively thick valve-seat ring M1. The space betweenthe lower end of the stack and the partition member M6 forms a chamber148 wherein the velocity head of the gas streams .introduced. throughinlets hit is substantially diminished before the streams pass upwardinto the stack proper through the opening formed by the seat ring ld'i.

The valve stem is constructed as shownin Fig. 3, comprising a hollowupper portion 38 and a solid lower portion 39, connected by the spider4s. The valve bonnet 3'5 is removably connected through its upper langei-ii to the connector M4. The bonnet is modified, however, to the extentof eliminating or blocking oil the bonnet inlets 43 12- 5 and ofreplacing the bleed steam port 53, extend lg radially partially through.the flange with a port communicating directly with the bonnet chamber. Afurther modification is made by replacing insulation casing 5% with ashorter cylindrical member lei extending into the chamber i le adistance about equal to the thickness of insulation material I52 appliedto the walls of the chamber Hi8 and the outer surface of the valve guidesleeve The valve .member is provided with a plug-type head E53 seatingagainst the ring M1, and "is operated axially to move the head toward oraway from its seat by suitable operating devices, such as those shown inFig. 1. A breakaway connection, such as that illustrated in Figs. 2 and3, may be provided to accommodate expansion of the valve stem. Or, aspring connection, such as that shown in Fig. in may be employed, sincethe major expansion forces to be contended with arise through thedifferential expansion between the valve stem and the member Hit. Ineither case, the amount of movement to be allowed for in the springconnection relatively small.

The use of the present valve for line gas control in the mannerillustrated has several advantages not found in the valves usuallyemployed in such connection. For one thing there is a constanteoncentricity of the hue gas stream with respect to the conduit or stackat all times, thus preventing impingement of the high velocity stream asit emerges from the valve port upon the walls of the conduit or othervalve parts. another is the lessening of the probability of erosion ofthe valve itself, since direction changes of the line gas stream arekept to a minimum, ch wear does inevitably occur is distributed equallyaround the periphery of the plug any wear in the plug or seat maycompensated for by providing an increased operating stroke for the valvestem. thus permitting the plug to be advanced into the ope -ing as weartakes place. Wear upstream of the valve is not expected to be so *ioussince velocities are relatively lower. Other advantages are to be foundin the ease of installation, and removal, since the valve is supported aunit in the lower connector or nozzle by a single bolted fiangeconnection, the lower costs of fabrication,

and the savings in material and labor by the elimination of the supportsusually required to support the overhang of the valve operator when thevalves are arranged in horizontal position.

By reason of the improvements of the present invention, it has beenpossible to obviate many of the disadvantages present in devicescommonly employed for the purpose of controlling catalyst flow into orout of internal transfer lines, and for controlling flue gas flowthrough a stack. By our invention We have been able to eliminate theelaborate and costly expansion devices normally required for carrierlines of any considerable length, and to minimize the flexible couplingarrangements normally required in the oil inlet connections when thecontrol valve is permitted to move under the expansion forces exerted bythe transfer lines. tage in the construction of the present invention isthe considerable saving in energy required to operate the valve stemthrough its various packing glands or stufling-boxes obtained by havingthose positions of the valve stem which move within the packed glandsconstructed of minimum circumference, so that frictional forces may bereduced to a minimum. In connection with its application to control ofdue gas discharge through a stack, the valve provides simplicity andeconomy of operation and reduced construction costs.

We claim:

1. In a fluidized catalyst conversion system in which fluids arecontacted with erosive entrained solids at high temperatures within alarge contacting chamber, and in which said fluids, containing erosiveentrained solids, are flowed from said chamber into the inlet of aconduit together with a second fluid introduced into said conduit froman external source, a unitary removable valve assembly for controllingthe flow of solids from said chamber into said conduit and forsimultaneously introducing fluid into said conduit, which includes: ahousing adapted to be demountably attached to the external surfaces ofsaid chamber and aligned with said conduit inlet, said housing having aninternal section projecting into the high temperature region within saidchamber and an external section projecting outside of said chamber; ahollowstem plug valve reciprocable in said internal section of saidhousing and adapted to enter said conduit inlet and having saidho1low-stem in open communication with the interior of said conduitthrough an orifice in the plug end; packing means in the lower part ofthe external section of said housing; actuating rod means constitutingan extension of said hollow-stem valve means and connected to saidhollow-stem valve and reciprocable in said packing along an axial path,said actuating rod means having a crosssection substantially less thanthe cross-section of said hollow-stem portion of said hollow-stem valvemeans, and substantially less than the interior cross-section of saidhousing to provide an annular space within the external section of saidhousing, said annular space being in open communication with said hol owstem; coupling means on said external portion of said housing adapted tobe connected to said external source of said second fluid forintroduction into said conduit by way of said annular space, saidhollow-stem, and said orifice in said plug valve; positioning means incooperative engagement A further advanwith said actuating rod means toregulate the position of said hollow-stem valve along its path ofmovement; and a spring connection securing said positioning means tosaid external portion of said housing, said positioning means beingmoveable as a unit with said hollow-stem and its extension away fromsaid tubular housing along said axial path against the action of saidspring upon the application of downward forces against said valve meansin excess of predetermined maximum.

2. In a fluidizedcatalyst conversion system in which a finely dividedsolid catalyst at elevated temperature is continuously circulatedbetween reaction and regenerating steps in separate reaction andregeneration chambers by means of a transfer fluid, one superimposedabove the other, means for controlling the circulating flow of solid-sbetween said chambers which includes: a downilow conduit and an upfiowconduit extending downwardly from said upper chamber into said lowerregion of said lower chamber and providing communication between saidupper and lower chambers, and terminating at their lower ends in valveseats; a pair of valve housings demountably attached to the exterior ofthe bottom of said lower chamber, each. of said valve housings beingprovided with a portion projecting upwardly into said lower chamber andpro vided with an internal passage in alignment with said valve seats; apair of plug valves vertically reciprocable in said valve housings andadapted to seat on said valve seats of said downfiow and upflow conduitsrespectively, said upflow conduit plug valve being provided with ahollowstem passage terminating at its upper end in a nozzle opening intothe interior of said upfiow conduit; means for introducing said transferfluid into the hollow-stem of said reciprocable plug valve forintroduction into said upfiow conduit by way of said nozzle opening inthe upper end of said plug valve; actuating rod means connected to saidhollow-stem below said transfer fluid introducing means and of across-section substantially less than the cross-section of saidhollow-stem; and packing means surrounding a portion of the length ofsaid actuating rod means to permit said actuating rod means and saidhollow-stem to reciprocate within their housing.

3. In a fluidized catalyst conversion system in which fluids arecontacted with erosive entrained solids at high temperatures within alarge contacting chamber, and in which said fluids, containing erosiveentrained solids, are flowed from said chamber into the inlet of aconduit together with a second fluid introduced into said conduit froman external source, a unitary removable valve assembly for controllingthe ilow of solids from said chamber into said conduit and forsimultaneously introducing fluid into said conduit, which includes: ahousing adapted to be demountably attached to the external surfaces ofsaid chamber and aligned with said conduit inlet, said housing having anintegral section projecting into the high temperature region within saidchamber and an external section projecting outside of said chamber; ahollow-stem plug valve reciprocable in said internal section of saidhousing and adapted to enter said conduit inlet and having saidhollow-stem in open communication with the interior of said conduitthrough an orifice in the plug end; packing means in the lower part ofthe external section of said housing; actuating rod means connected tosaid hollow-stem valve and reciprocable in said packing, said actuatingrod means having a cross-section substantially less than thecrosssection of said hollow-stem portion of said hollow-stem valvemeans, and substantially less than the interior cross-section of saidhousing to provide an annular space within the external section of saidhousing, said annular space being in open communication with saidhollow-stem; coupling means on said external portion of said housingadapted to be connected to said external source of said second fluid forintroduction into said conduit by way of said annular space, saidhollow-stem, and said orifice in said plug valve; and positioning meansin cooperative engagement with said actuating rod means to regulate theposition of said hollow-stem valve along its path of movement.

HAROLD KERSHAW.

EDWARD D. DOWLING.

References Cited in the file of this patent UNITED STATES PATENTS NumberNumber Name Date Kennedy June 21, 1892 Von Porat Oct. 21, 1919 KniskernFeb. 7, 1928 Hufi July 31, 1928 Still Feb. 11, 1936 McKinnon Mar. 16,1937 White Oct. 19, 1943 Angell Dec. 30, 1947 Hengstebeck Dec. 28, 1948Johnson Nov. 15, 1949 FOREIGN PATENTS Country Date Great Britain 1900

3. IN A FLUDIZED CATALYST CONVERSION SYSTEM IN WHICH FLUIDS ARECONTACTED WITH EROSIVE ENTRAINED SOLIDS AT HIGH TEMPERATURES WITHIN ALARGE CONTACTING CHAMBER, AND IN WHICH SAID FLUIDS, CONTAINING EROSIVEENTRAINED SOLIDS, ARE FLOWED FROM SAID CHAMBER INTO THE INLET OF ACONDUIT TOGETHER WITH A SECOND FLUID INTRODUCED INTO SAID CONDUIT FROMAN EXTERNAL SOURCE, A UNITARY REMOVABLE VALVE ASSEMBLY FOR CONTROLLINGTHE FLOW OF SOLIDS FROM SAID CHAMBER INTO SAID CONDUIT AND FORSIMULTANEOUSLY INTRODUCING FLUID INTO SAID CONDUIT, WHICH INCLUDES: AHOUSING ADAPTED TO BE DEMOUNTABLY ATTACHED TO THE EXTERNAL SURFACES OFSAID CHAMBER AND ALIGNED WITH SAID CONDUIT INLET, SAID HOUSING HAVING ANINTEGRAL SECTION PROJECTING INTO THE HIGH TEMPERATURE REGION WITHIN SAIDCHAMBER AND AN EXTERNAL SECTION PROJECTING OUTSIDE OF SAID CHAMBER; AHOLLOW-STEM PLUG VALVE RECIPROCABLE IN SAID INTERNAL SECTION OF SAIDHOUSING AND ADAPTED TO ENTER SAID CONDUIT INLET AND HAVING SAID HOLLOWSTEM IN OPEN COMMUNICATION WITH THE INTERIOR OF SAID CONDUIT THROUGH ANORIFICE IN THE PLUG END; PACKING MEANS IN THE LOWER PART OF THE EXTERNALSECTION OF SAID HOUSING; ACTUATING ROD MEANS CONNECTED TO SAIDHOLLOW-STEM VALVE AND RECIPROCABLE IN SAID PACKING, SAID ACTUATING RODMEANS HAVING A CROSS-SECTION SUBSTANTIALLY LESS THAN THE CROSSSECTION OFSAID HOLLOW-STEM PORTION OF SAID HOLLOW-STEM VALVE MEANS, ANDSUBSTANTIALLY LESS THAN THE INTERIOR CROSS-SECTION OF SAID HOUSINGPROVIDE AN ANNULAR SPACE WITHIN THE EXTERNAL SECTION OF SAID HOUSING,SAID ANNULAR SPACE BEING IN OPEN COMMUNICATION WITH SAID HOLLOW-STEM;COUPLING MEANS ON SAID EXTERNAL PORTION OF SAID HOUSING ADAPTED TO BECONNECTED TO SAID EXTERNAL SOURCE OF SAID SECOND FLUID FOR INTRODUCTIONINTO SAID CONDUIT BY WAY OF SAID ANNULAR SPACE, SAID HOLLOW-STEM, ANDSAID ORIFICE IN SAID PLUG VALVE; AND POSITIONING MEANS IN COOPERATIVEENGAGEMENT WITH SAID ACTUATING ROD MEANS TO REGULATE THE POSITION OFSAID HOLLOW-STEM VAVE ALONG ITS PATH OF MOVEMENT.